Field of the Invention
The present invention relates to a battery cooling system for a vehicle. More particularly, the present invention relates to a battery cooling system that makes a heat pump system and a cooling system for an electric device, circulating a coolant to the electric device including a motor integrated with each other in an electric vehicle or a hybrid vehicle, and warming up or cooling down a battery using a refrigerant and a coolant according to a mode of the vehicle.
Description of Related Art
In general, an air conditioning device for a vehicle includes an air conditioning system that circulates a refrigerant to heat or cool the inside of the vehicle.
Such an air conditioning means is provided to maintain a pleasant indoor environment by maintaining an indoor temperature of the vehicle with an appropriate temperature regardless of an external temperature change, and is configured to warm or cool the inside of the vehicle through heat-exchange by an evaporator while a refrigerant discharged by driving of a compressor is being circulated back to the compressor through a condenser, a receiver dryer, an expansion valve, and the evaporator.
That is, a high-temperature high-pressure gas-state refrigerant compressed from the compressor is condensed through the condenser and then evaporated in the evaporator through the receiver dryer and the expansion valve to thereby decrease an indoor temperature and humidity.
Meanwhile, as a concern about energy efficiency and environmental contamination problems has been increased, a development and research for an environmentally-friendly vehicle that can replace an internal combustion engine vehicle has been requested, and such an environmentally-friendly vehicle can be classified into an electric vehicle driven using a fuel cell or electricity as a power source and a hybrid vehicle driven by an engine or a battery.
Among the environmentally-friendly vehicles, no additional heater is used in the electric vehicle or the hybrid vehicle unlike an air conditioning device of a typical vehicle, and an air conditioning device applied to the environmentally-friendly vehicle is typically called a heat pump system.
In the case of the electric vehicle using a fuel cell, chemical reaction energy of oxygen and hydrogen is converted into electric energy to generate driving force, and during this process, heat energy is generated by chemical reaction in the fuel cell, and as a result, it is necessary to effectively remove generated heat to secure performance of the fuel cell.
Even in the hybrid vehicle, the driving force is generated by driving the motor by using electricity supplied from the fuel cell or the electric battery together with the engine that is actuated with general fuel, and as a result, the performance of the motor can be secured only by effectively removing the heat generated from the fuel cell or the battery, and the motor.
Accordingly, a cooling means for an electric device, a heat pump system, and a battery cooling system should be configured as individual closed circuits respectively so as to prevent heat generation from a motor, an electric device, and a battery including a fuel cell in a conventional hybrid vehicle or electric vehicle.
Thus, the size and weight of a cooling module disposed in a front portion of the vehicle are increased, and layouts for connection wires through which a refrigerant or a coolant is supplied to the heat pump system, the cooling means, and the battery cooling system from the inside of an engine room are complicated.
Further, for optimal performance of the battery, a battery cooling system that warms up or cools down the battery according to a state of the vehicle is separately provided, and thus a plurality of valves are provided for connection with the respective connection wires and noise and vibration caused from frequent opening/closing of the valves is transferred to the inside of the vehicle, thereby deteriorating riding comfort of the vehicle.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.